Breast mri for diagnosis and staging of breast cancer

Breast magnetic resonance imaging (MRI) has been a very fast developing tool for the assessment of breast cancer and quickly moved from research to clinical settings. It is being used to evaluate patients with specific indications and as a screening tool for high-risk patients. The value of breast MRI arises from its very high sensitivity in detecting breast cancer but more importantly from its ability to functionally assess physiological and biochemical properties of breast tissue, thus helping in the management of breast cancer, including the assessment of the extent of disease, the detection of contralateral disease, and the evaluation of treatment response. Response to treatment has been traditionally assessed based on gross tumor size change, a parameter that has been shown to have limitations in the accurate prediction of the treatment response and outcome. MRI offers functional methods to aid treatment response assessment that better reflect the viability of tumor and tumor burden versus just size changes. Understanding the indications for breast MRI, diagnostic criteria utilized to detect and characterize breast cancer, and technical challenges are important in both clinical and research settings. In this chapter we discuss the utilization of breast MRI in breast cancer diagnosis and staging, including the review of patterns of enhancement and principles of pharmacokinetic modeling for dynamic contrast-enhanced MRI, application of diffusion-weighted imaging and MR-guided breast biopsy, as well as review of technical considerations for optimization of image acquisition and assessment of treatment response.